Production of polyvinyl alcohol having improved dyeability and composition therefor including polymers containing basic nitrogen



United States Patent Japan No Drawing. Filed Mar. 18, 1960, Ser. No. 15,799

Claims priority, application Japan, Mar. 20, 1959, 34 8,626 5 Claims. '2 ;(Cl. 260898) This invention relates to a process of producing fibers of polyvinyl alcohol and polyvinyl alcohol derivatives and is more particularly concerned with a process of forming such fibers which are characterized by desirable properties.

As described in US. patent application Ser. No. 85 6,334, filed December 1, 1959, now Patent No. 3,007,228 the dyeability of polyvinyl alcohol fibers can be markedly increased by spinning the fibers from a mixture of an emulsified polymer formed from basic monomers and a water solution of polyvinyl alcohol. When fibers spun from such a mixture are subjected to benzalization, which has the effect of significantly improving the elasticity of polyvinyl alcohol, fibers can be obtained which have ex cellent elastic elongation and dyeability without showing any significant drop in dye-absorption. This is substantially different from the results obtained by mixed spinning of water-soluble polymers containing basic nitrogen as heretofore practiced.

It is thus an object of this invention to provide a process for producing fibers of polyvinyl alcohol and polyvinyl alcohol derivatives having high heat-resistance and desirable mechanical properties at least equal to fibers produced solely from polyvinyl alcohol, yet characterized by a particularly high dyeability.

In accordance with this invention, spinning of fibers is effected from a spinning fluid prepared by dispersing in a water solution of polyvinyl alcohol an emulsion or fine powder of polymer which has had basic nitrogen introduced into the molecule by first introducing the cyano radical and then causing the fine powder or emulsion containing the cyano radical to undergo chemical reaction to convert it to basic nitrogen while the emulsified or pulverized state is retained. We have studied extensively the methods of manufacturing emulsions of polymers which could be used to produce fibers having the abovementioned desirable characteristics, and we have succeeded in achieving this result eifectively and economically from emulsions or fine powders of polymers which contain basic nitrogen and are water-insoluble by causing emulsions Or fine powders of polymers having cyano radical to undergo chemical reaction while in their emulsified or pulverized form, so as to convert the cyano radical into a functioning radical having basic nitrogen.

It has been found that the emulsions or fine powders produced by the method of this invention make it possible to achieve the advantageous results described in said application Ser. No. 856,334 now Patent No. 3,007,228 without difiiculty, when a spinning fluid is prepared by incorporating the emulsions or fine powder produced by the method of this invention in a water solution of polyvinyl alcohol.

We have also found that when subjected to thermal stretching, which is efiective to promote hot water-resistance, resilience and elasticity, the fibers containing solid particles produced by this invention not only do not lose any of their dyeability but their dyeability is enhanced, the

3,161,699 Patented Dec. 15, 1964 enhancement being greater the greater the percentage of thermal stretching. It has also been found that when thermal contraction is effected upon the fibers, which is effective to promote the knotting strength of the fibers, the dyeability of the fibers is increased as compared with the result when heat-treatment is effected at a constant yarn length, which is directly contrary to the behavior of ordinary polyvinyl alcohol fibers or of fibers produced by mixed spinning of a water-soluble polymer as attempted in the past. The reason for this behavior is not completely understood. However, when examined by the electron microscope, the surface of fiber is seen to exhibit large cracks along the solid particles. Based on these observations, it is believed that the solid particles are difiicultly influenced by the structure of the polyvinyl alcohol portion of the fiber, and are in a state which allows the permeation of dyestuffs. On the other hand, as described in said application Ser. No. 856,334, now Patent No. 3,007,228 the size of the solid particles in a stable spinning fluid which can be spun without any difiiculty, and hence those P CC contained in the spun fiber, is usually but a few ,u. According to the method of this invention, it is possible to.

obtain particle sizes ranging from 0.01 1. to 10 1.. It has been found that the greater the particle size, the more significant will be the increase in dyeability after benzalization. It is believedthat the reason for this is the fact that the larger the particle size, the more difficult it will be to affect it by the structure of the benzalized portion of polyvinyl alcohol. However, when the particle size or the size of coagulation product is significantly large, it will give rise to disadvantages such as broken yarns or fluffy yarns in the spinning process with subsequent deterioration in the mechanical properties of the fiber. Therefore, it is important to restrict the size of the particles to a value of 30;; or below. The emulsified reaction product or the spinning fluid containing fine particles produced in accordance with the method of this invention is stable, and contains no particle or fine powder of a magnitude of 101.6 or larger, which is sufiicient to attain a smooth spinning operation.

The amount of basic nitrogen to be introduced by chemical reaction, is suitably 0.2% or more, and the ratio of mixing of such polymers with polyvinyl alcohol is adequate if it produces a mixture of a 0.05-2% content of basic nitrogen. By such admixture, a marked increase of the dyeability of the produced fibers is noted with direct cotton dyes and with acid wool dyes, whereas any drop in hot water-resistance, heat-resistance and other mechanical properties is very slight.

The emulsions of polymers containing the cyano radical to be used in the present invention can easily be prepared by emulsion polymerization of monomers containing the cyano radical in the presence of conventional surface-active agents or protective colloids, or by emulsion co polymerization between the above-mentioned monomers and monomers containing or not containing the cyano radical. It is also possible to obtain emulsions of such polymers by a process in which, after a polymer containing the cyano-radical is dissolved in an organic solvent which is immiscible with water, the solution is mixed with and dispersed in a water solution which contains a surface-active agent or a protective colloid, and then the organic solvent is removed. In general, various known types of anionic, non-ionic, and cationic surface-active agents are suitably used. However, when basic nitrogen is introduced by chemical reaction, an anionic surfaceactive agent often may form bond with the introduced basic nitrogen to coagulate the emulsion. Hence, it is preferred to use a non-ionic surface-active agent such as polyoxyethylenedodecyl ether or a cationic surfaceactive agent such as dodecyltrimethyl-ammonium chloride. As the protective colloid, water-soluble polymers 3 such as polyvinyl alcohol, partially-saponification products of polyvinyl acetate, gelatin, soluble starch, and aminoacetalized polyvinyl alcohol, are suitably used. In this case, it is also desirable that a non-ionic or cationic polymer be used for the reason referred to in connection with the surface-active agent. As described in application Serial No. 856,334, now Patent No. 3,007,228 the emulsion of the polymer obtained by co-polymerization between the monomer containing quaternary nitrogen and the monomer having amino group exhibits significant stability against various salts, and hence it will not coagulate even when salts are used in such chemical reaction. Thus, it is possible to carry out the chemical reaction while maintaining the emulsified state. However, in effecting the chemical reaction in general, coagulation does sometimes take place when a salt is used. In order to avoid this, various means may be employed. For instance, such coagulation may be avoided when the chemical reaction is carried out by preparing a mixture corresponding to the spinning'fiuid consisting of an emulsion of the polymer containing the cyano radical with a water solution of polyvinyl alcohol.

As monomers containing the cyano radical, acrylonitrile, methacrylonitrile, allylcyanide, vinylidene-cyanide, a-cyanovinylacetate, and the like are suitably used. As monomers containing no cyano radical, but which can copolymerize with the above monomers, there are suitably used styrene, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl benzoate, :butadiene, methyl acrylate, methyl methacrylate, vinylpyrrolidone, ethyl methacrylate, acrylamide, acrolein, methylvinylketone, allylamide, allyl acetate, allyl chloride, diallylphthalate, divinylbenzene, 2- vinylpyridine, 4-vinylpyridine, Z-methyI-S-Vinylpyridine, 5-ethyl-2-vinylpyridine, 2-methyl-5-vinylpyridiniumethylbromide, 4-vinylpyridiniummethyl-methylsulfate, dimethylaminoethyl-methacrylate, allylpyridiniumchloride, and the like.

As emulsions and fine powders of polymers containing the cyano radical there may be used, in addition to the polymerization products or co-polyrnerization products of these monomers, Streckers reaction products obtained by addition reaction of ammonium on the emulsified polymer of methylvinylketone, cyano-ethylated polyvinyl alcohol produced by the action of acryonitrile, acetalized polyvinyl alcohol produced by the action of fi-cyanopropionaldehyde, p-cyanobenzaldehyde, and the like which contain the cyano radical, or an emulsion or fine powder of mixed acetalized or etherified polyvinyl alcohol produced by the action of the aforementioned products and aldehydes having no cyano radicals such as formaldehyde, and emulsions and fine powders of polymers to which the cyano-radical has been introduced by chemical reaction.

Various chemical reactions may be employed to introduce basic nitrogen, such as the amidoximation reaction with hydroxylamide, the formation of amidine by primary amines such as methylamine, ethylamine, cyclohexylamine, ethylenediamine, and the like, the reaction of hydrazine, contact reduction by means of hydrogen, and the like. The mechanism of the reaction of hydrazine on the cyano radical, is not definitely known, but a reaction similar to that of hydroxylamine, wherein there is formed the aminotriazole ring, can be presumed. In any event, in view of its effect to improve the dyeability of the fibers in the persent invention, it is clear that it is etfective to introudce basic nitrogen.

The fibers spun by the method of this invention can be subjected to heat-treatment, hot-stretching, and insolubilization in the same manner as fibers produced from polyvinyl alcohol alone. For the purpose of insolubilization, not only acetalization by the use of aldehydes such as formaldehyde, acetaldehyde, butyraldehyde, nonylaldehyde, benzaldehyde, monochlorobenzaldehyde, naphthaldehyde, malonaldehyde, glutaldehyde, is suitably efiected, but treatments by means of inorganic substances such as titanation, chroming, and the like can be employed.

In accordance with this invention, it is also possible to carry out spinning fluids containing fine particles of polymers as described above but to which have been added water-soluble polymers such as soluble starch, aminoacetalized polyvinyl alcohol, polyvinylpyrrolidone, pigments such as titanium oxide, oxide, salt-s such as zinc sulfate, sodium sulfate, and the like. Consequently, it is practicable to effect simultaneous improvements in transparency and in the form of the cross-section of the fibers, particularly in the case of wet-spinning.

The invention will be further understood from the following specific examples of practical application. However, it will be understood that these examples are not to be construed as limiting the scope of the present invention in any manner. In these examples, all parts are by weight.

Example 1 While a mixture of acrylonitrile (50 g.), 2-methyl-5- vinyl-pyridiniumethylbromide (20 g.), and water (330 g.) was stirred at 50 0., sodium bisulfite (0.3 g.) and then potassium persulfate (0.5 g.) were added, and the mixture polymerized for 4 hours. The emulsion thus produced was subjected to steam distillation, and was dialyzed in running water, whereby 650 g. of an emulsion of the polymer was obtained (Sample A). To 150 g. of Sample A was added 50 g. of a water solution containing hydroxylamine hydrochloride and then a water solution of polyvinyl alcohol (50 g.) and caustic soda (8 g.),

and the mixture reacted at 60 C. for 20 hours with stirring. During the reaction an emulsified condition was maintained so that basic nitrogen was introduced by an amidoximation reaction. The emulsified reaction product thus obtained was dialyzed, whereby 400 g. of emulsion of 4.5% concentration (Sample B) was obtained. Sample A (79 g.) was mixed with a water solution of polyvinyl alcohol (142.5 g.) to prepared a mixture having a 15% concentration. In like manner, Sample B (167 g.) was mixed with a water solution of polyvinyl alcohol (142.5 g.) to produce a mixture of 15% concentration. Wet-spinning of the two mixtures was then effected in a sodium sulfate coagulation bath. After heat-treatment under a constant yarn length at 240 C. for 10 sec., acetalization of the fibers from the two mix-. tures was etfected in a water solution containing 2% of monochlorobenzaldehyde, 10% of sulfuric acid and 50% of methanol at 60 C. for one hour. In order to make a comparison with Samples A and B, a water solution of polyvinyl alcohol alone (Sample C) was subjected to spinning, heat-treatment and acetalization under the same conditions used in treating Samples A and B, and all three samples were dyed. The following table shows the vari ous hemical and physical properties of Samples A, B and Degree of acetalization (percent) 22. Strength (percent/denier) Shrinkage in water 0.) (percent) Softening point by dry heating O.) Elasticity at 3% elongation (percent)- Rate of absorption of acid dyes (percent) Example 2 To a mixture consisting of acrylonitrile (500 g), polyvinyl alcohol (100 g.) and water (3 kg), there were.

added sodium bisulfite (2.5 g.) and potassium persulfate (4 g.), and polymerization was effected at 60 C. for 3 hours. After steam-distillation, 5.5 kg. of an emulsion containing 510 g. of polymer was' obtained. To this emulsion (1.64 kg.) hydrazine hydrate (222 g.) was added, and reaction was effected at 60 C. for 48 hours. The reaction mixture was then subjected to dialysis, whereby 1.7 kg. of an emulsion of 8.8% concentration was obtained. As seen in the electron microscope, the particle size of the polymer was about 0.2 in diameter. This polymer was mixed with polyvinyl alcohol (1.35 kg.) to prepare a spinning fluid of 35% concentration, which was dry spun by forcing it out into the air through a spinning nozzle having 20 pores 0.3 mm. in diameter. The thus-produced fiber was stretched in a continuous process by 500% at 220 C., and then shrunk by 20% at 225 C.

Some of the fibers were then formalized in a Water solution containing 5% of formaldehyde, and 15% of sulfuric acid and 15% of sodium sulfate to produce a Sample D. The rest of the fibers were benzalized in a water solution containing 3% of benzaldehyde, of sulfuric acid and 40% methanol to produce a Sample E. The degree of acetalization for Sample D was 38.1% and for Sample E, 27.5%. The shrinkage when treated in water at 100 C.'f0f 1 hour was 2.3% for Sample D,

and 5.5% for Sample E, showing sufficient hot-water resistance in both cases. Elasticity at 3% elongation was 53% for Sample D and 81% forv Sample E, the benzalized fiber being particularly superior in this property. When these fibers were dyed with an acid dye under the same conditions set forth in Example 1, they absorbed the acid dye completely. When nippon fast violet BB (Colour Index No. 27905) (direct dye) of 2% was used with sodium sulfate (10% based on the weight of fiber) for dyeing at 90 C. for 2 hours, the dye was absorbed 95% in Sample D and 75% in Sample E. In both cases, a saturated and bright color was obtained.

Example 3 Nitrogen was passed through a mixture of methacrylonitrile (130 g.), methyl methacrylate (20 g.), polyvinyl alcohol (50 g.), dodecyltrimethylammonium chloride g.) and water (1 kg.) to replace the air with nitrogen. Then a water solution of cerium ammonium nitrate (0.4 g.) and nitric acid (0.5 g.) was added with stirring, and polymerization was effected at 30 C. for 3 hours. Unpolymerized substances were removed by steam-distillation, whereby 1.4 kg. of an emulsion containing 165 g. of polymer was obtained. The polymerization product obtained was a so-called graft-copolymer in which the side-chain of the co-polymer of methacrylate is combined with the stem of polyvinyl alcohol. 15 parts of this product were mixed with 100 parts of polyvinyl alcohol so as to prepare a mixture having a total polymer concentration of 12.5%. While this mixture was being stirred, an equivalent volume of hydroxylamine formate was added. After the mixture was maintained at 80 C. for 24 hours, wet-spinning was carried out under the same conditions described in Example 1. The fibers were then hot-stretched at 230 C. for 30 sec., during which treatment the yarn was stretched by 180%, and then heat-treatment was effected at constant yarn length at 235 C. for 30 min.

Three samples of these fibers were benzalized as described in Example 1, to provide 16.9%, 22.1% and 28.7% benzalization respectively, and dyeing tests were conducted upon the three samples in accordance with the procedure of Example 1. It was observed that acid brilliant scarlet 3R (Colour Index No. 16255) (acid dye) (4% based on the fiber weight) was fully absorbed by the three samples. In addition all of the fibers had a feel with richer resilience as compared with ordinary polyvinyl alcohol fibers.

6 Example 4 An aqueous mixture containing 3% of polyvinyl alcohol, 3% of formaldehyde and 50% of sulfuric acid was gradually raised in temperature starting 30 C. to 60 C., and at the latter temperature it was stirred for 2 hours. Then the temperature was lowered to 40 C., and a water solution of 1% of a cation surface active agent was slowly added and the partially formalized product was obtained in finely-divided form. After adding 3% of B-cyanopropionaldehyde, and stirring at 70 C. for 3 hours, the reaction mixture was filtered and washed. The fine pow:

der thus obtained was treated in a water solution consisting of 7% hydroxylamine hydrochloride and 4% caustic soda at 60 C. for 6 hours, and after salts had A mixture of acrylonitrile (95 g.), divinylbenzene 5 g.), polyvinyl alcohol (20 g.), dodecyltrimethylammonium chloride (8 g.), ammonium persulfate (1 g.), sodium bisulfite (1 g.) and water (500 g.) were stirred at 60 C. for 4 hours, and after steam-distillation, an emulsified copolymer of acrylonitrile and divinylbenzene was obtained with a percent polymerization of 92%. To this, hydroxylamine (100 g.) was added and, after allowing the reaction mixture to stand to complete reaction at 60 C. for 24 hours, the substances which had not reacted were removed by dialysis. 3 par-ts of the reaction products in emulsion form thus obtained were mixed with 97 parts of polyvinyl alcohol and the mixture was wet-spun in the manner described in Example 1. The fibers were divided into four Samples H, I, J, and K. Heat-treatment at constant yarn length was applied to Sample H; hot-stretching for 50% and then heat-treatment at constant yarn length were applied to Sample I; Sample J was subjected to hot-stretching for 100% and then heat-treatment at constant yarn length; and 100% hotstretching and then 20% hot-shrinking were applied to Sample K, after which benzalization was carried out to a degree of benzalization of 2426%.

The chemical and physical properties of these samples are set forth in the following table. In the case of the samples subjected to hot-stretching and hot shrinking, the elevation in dyeability was particularly significant. When the fiber surface of Sample K was examined, the cracks were noted to be present along the particles of about 0.2; diameter.

Rate of hot-stretching (percent) 0 50 100 100 Rate of hot-shrinking (percent) 0 0 0 20 Shrinkage in water (100 0.) (percent) 8.0 7.5 5.4 5. 0 Strength (gJdenier) 3. 5 5. 5 6. 6 6. 3 Knotting strength (g./denier) 2. 5 3.3 3. 5 4.4 Elasticity at 3% elongation (percent) 81 87 90 85 Rate of absorption of acid dyes (percent) 78 91 96 ample 2 and the solution was allowed to stand at 60 C. for 20 hours. The reaction product had a nitrogen content of 18.8% and was in the form of an emulsion. The emulsion particles were dyed with an acid dye.

This emulsion was mixed with an amount of polyvinyl alcohol such that the nitrogen percentage of the polymer in the mixture was 1.2%. Then the emulsion was dryspun, and the fibers were subjected to hot-stretching, hotshrinking, and acetalization. The thus-treated fibers exhibited excellent dyeability with various types of acid dyes and direct dyes.

It will be understood that, unless otherwise indicated, conventional dry-spinning or wet-spinning operations are employed in producing the fibers and subsequent heat treatment, stretching and relaxation are effected in accordance with known techniques. Similarly, conventional apparatus is employed in carrying out the process of this invention including conventional mixing and emulsifying units, spinning devices and fiber treating apparatus. The conditions and the relative relationships set forth in the examples are those preferred in carrying out the process of the invention but it will be understood that other conditions and relationships may be used within the scope of the invention. Similarly, conventional dyeing techniques and apparatus are suitably employed upon the fibers produced by the process of this invention.

It will also be understood that various changes and modifications may be made without departing from the scope of the invention as defined in the appended claims and it is intended, therefore, that all matter contained in the foregoing description shall be interpreted as illustrative only and not as limitative of the invention;

We claim:

1. A method of manufacturing a polyvinyl alcohol fiber having improved dyeability which comprises,

preparing an aqueous spinning fluid containing dissolved polyvinyl alcohol and dispersed particles of a water-insoluble basic-nitrogen containing polymeric material,

said dispersed particles of said polymeric material in said spinning fluid being in finely-divided form and having a particle size of from about 0.01 to about 4; said polymeric material comprising the reaction product obtained by the reaction of cyano groups in a compound selected from the group consisting of (1) a homopolymer containing cyano groups, (2) and a copolymer containing cyano groups, with a reagent selected from the group consisting of hydroxylamine, primary amines, and hydrazine, whereby said reaction results in the conversion of said cyano groups in said compound to form an'aminotriazole ring in the case of hydroxylamine and hydrazine and to form an amidine in the case of said primary amines, said basic nitrogen in said polymeric material due to the presence of said aminotriazole ring and said amidine,

and where the number of cyano groups in said com pound is suflicient to produce a said polymeric material containing at least about 0.2% basic nitrogen by said reaction of said cyano groups and said reagent,

said homopolymer being prepared by the homopolymerization of a monomer selected from the group consisting of acrylonitrile, methacrylonitrile, allyl cyanide, vinylidenecyanide, and a-cyanovinylacetate,

said copolymer containing cyano groups being a copolymer prepared by the copolymerizaion of a monomer selected from the group consisting of acrylonitrile, methacrylonitrile, allyl cyanide, vinylidenecyanide, and a-cyanovinylacetate,

and a comonomer selected from the group consisting styrene, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl benzoate, butadiene, methyl acrylate, methyl methacrylate, vinylpyrrolidone, ethyl methacrylate, acrylamide, acrolein, methylvinyl-ketone, allylamide, allyl acetate, allyl chloride, diallylphthalate, divinylbenzene, Z-vinylpyridine, 4-vinylpyridine, Z-methyl-S-vinylpyridine, S-ethyl-Z-vinylpyridine, 2-methyl-5-vinylpyridiniumethyl-bromide, 4-vinylpyridinium-ethyl-methylsulfate, dimethylaminoethylmethacrylate, and allylpyridiniumchloride;

and preparing a polyvinyl alcohol fiber from said aqueous spinning fluid by spinning wherein said aqueous fluid contains a suificient amount of said dispersed Water-insoluble polymeric material whereby said prepared polyvinyl alcohol fiber contains an amount of basic nitrogen that is at least about 0.05% due to the presence of said polymeric material in said prepared fiber.

2. A method according to claim 1, wherein the amount of said dispersed water-insoluble polymeric material in said aqueous fluid is of a sufficient amount whereby said prepared polyvinyl alcohol fiber contains from about 0.05% to about 2% basic nitrogen due to said polymeric material in said prepared polyvinyl alcohol fiber.

3. A method according to claim 1, wherein said polymeric material is prepared from the'homopolymer prepared by the homopolymerization of acrylonitrile.

4. A method of manufacturing a polyvinyl alcohol fiber having improved dyeability which comprises,

preparing a water-insoluble basic-nitrogen-containing polymeric material by the reaction of a compound selected from the group consisting of (1) a homopolymer containing cyano groups, (2) and a copolymer containing cyano groups, with a reagent selected from the group consisting of hydroxylamine, primary amines, and hydrazine, whereby said reaction results in the conversion of said cyano groups in said compound to form an aminotriazole ring in the case of hydroxylamine and bydrazine and to form an amidine in the case of said primary amines, said basic nitrogen in said polymeric material due to the presence of said aminotriazole ring and said amidine,

and where the number of cyano groups in said compound is suflicient to produce a said polymeric material containing at least about 0.2% basic nitrogen by said reaction of said cyano groups and' said reagent,

said homopolymer being prepared by the homopolymerization of a monomer selected from the group consisting of acrylonitrile, methacrylonitrile, allyl cyanide, vinylidenecyanide, and a-cyanovinylacetate, said copolymer-containing cyano groups being a copolymer prepared by the copolymerization of a monomer selected from the group consisting of acrylonitrile, methacrylonitrile, allyl cyanide, vinylidenecyanidc, and u-cyanovinylacetate,

and a comonomer selected from the group consisting of styrene, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl benzoate, butadiene, methyl acrylate, methyl methacrylate, vinylpyrrolidone, ethyl methacrylate, acrylamide, acrolein, methylvinyl-ketone, allylamide, allyl acetate, allyl chlo- (ride, diallylphthalate, divinylbenzene, 2-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, 5-ethyl-2-v-inylpyridine, 2-methyl-5-vinylpyridiniumethyl-bromide, 4-vinylpyridiumethylmethylsulfate, dimethylaminoethylmethacry late, and allylpyridiniumchloride;

dispersing said polymeric material in an aqueous solution of polyvinyl alcohol to produce an aqueous spinning fluid containing dispersed particles of said polymeric material and where said dispersed particles have a particle size from about 0.01 1 to about 10,; and preparing a polyvinyl alcohol fiber from said aqueous spinning fluid by spinning wherein said aqueous fluid contains a sufiicientamount of said dispersed water-insoluble polymeric material whereby said prepared. polyvinyl alcohol fiber contains an amount of basic nitrogen that is from about 0.05% to about 2% due to the presence of said polymeric material in said prepared fiber. 5. A spinning fluid for the manufacture of polyvinyl alcohol fibers having improved dyeability which comprises,

an aqueoues spinning fluid containing dissolved polyvinyl alcohol and dispersed particles of a water-insoluble basic-nitrogen containing polymeric material, said dispersed particles of said polymeric material in said spinning fluid being in finely-divided formand having a particle size of from about 0.0m to about 7% said polymeric material comprising the reaction product obtained by the reaction of cyano groups in a compound selected from the group consisting of (1) a homopolymer containing cyano groups, (2) and a copolymer containing cyano groups, with a reagent selected from the group consisting of hydroxylamine, primary amines, and hydrazine, whereby said reaction results in the conversion of said cyano groups in said compound to form an aminotriazole ring in the case of hydroxylamine and hydrazine and to form an amidine in the case of said primary amines, said basic nitrogen in said polymeric material due to the presence of said aminotriazole ring and said amidine, and where the number of cyano groups in said compound is sulficient to produce a said polymeric material containing at .least about 0.2% basic nitrogen by said reaction of said cyano groups and said reagent, said homopolymer being prepared by the homopolymerization of a monomer selected from the group consisting of acrylonitrile, methacrylonitrile, allyl cyanide, vinylidenecyanide, u-cyanovinylacetate, said copolymer containing cyano groups being a copolymer prepared by the copolymerization of a monomer selected group the group consisting of acrylonitrile, methacrylonitrile, allyl cyanide, vinylidenecyanide, and a-cyanovinylacetate, and a comonomer selected from the group consisting of styrene, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl benzoate, butadiene, methyl acrylate, methyl methacrylate, vinylpyrrolidone, ethyl methacrylate, acrylamide, acrolein, methylvinyl-ketone, allylamide, allyl acetate, allyl chloride, diallylphthalate, divinylbenzene, 2-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, 5-ethyl-2-vinylpyridine, 2-methyl-5-vinylpyridiniumethyl bromide, 4 vinylpyridiniumethyl methylsulfate, dimethylaminoethylmethacrylate, and allylpyridiniumchloride; and where polyvinyl alcohol fibers may be produced from said spinning fiuid by spinning and where said fibers contain from about 0.05% to about 2% basic nitrogen.

References Cited in the file of this patent UNITED STATES PATENTS 2,239,718 Izard Apr. 29, 1941 2,697,088 Stanin et al Dec. 14, 1954 2,895,786 Schlack July 21, 1959 

1. A METHOD OF MANUFACTURING A POLYVINYL ALCOHOL FIBER HAVING IMPROVED DYEABIITY WHICH COMPRISES, PREPARING AN AQUEOUS SPINNING FLUID CONTAINING DISSOLVED POLYVINYL ALOCOHOL AND DISPERSED PARTICLES OF A WATER-INSOLUBLE BASIC-NITROGEN CONTAINING POLYMERIC MATERIAL, SAID DISPERSED PARTICLES OF SAID POLYMERIC MATERIAL IN SAID SPINNING FLUID BEING IN FINELY DIVIDED FORM AND HAVING A PARTICLE SIZE OF FROM ABOUT 0.01$ TO ABOUT 10$; SAID POLYMERIC MATERIAL COMPRISING THE REACTION PRODUCT OBTAINED BY THE REACTION OF CYANO GROUPS IN A COMPOUND SELECTED FROM THE GROUP CONSISTING OF (1) A HOMOPOLYMER CONTAINING CYANO GROUPS, (2) AND A COPOLYMER CONTAINING CYANO GROUPS, WITH A REAGENT SEELCTED FROM THE GROUP CONSISTING OF HYDROXYLAMINE, PRIMARY AMINES, AND HYDRAZINE, WHEREBY SAID REACTION RESULTS IN THE CONVERSION OF SAID CYANO GROUPS IN SAID COMPOUND TO FORM AN AMINOTRIAZOLE RING IN THE CASE OF HYDROXYLAMINE AND HYDRAZINE AND TO FORM AN AMIDINE IN THE CASE OF SAID PRIMARY AMINES, SAID BASIC NITROGEN IN SAID PLOYMERIC MATERIAL DUE TO THE PRESENCE OF SAID AMINOTRIAZOLE RING AND SAID AMIDINE, AND WHERE THE NUMBER OF CYANO GROUPS IN SAID COMPOUND IS SUFFICIENT TO PRODUCE A SAID POLYMERIC MATERIAL CONTAINING AT LEAST ABOUT 0.2% BASIC NITROGEN BY SAID REACTION OF SAID CYANO GROUPS AND SAID REAGENT, SAID HOMOPOLYMER BEING PREPARED BY THE HOMOPOLYMERIZATION OF A MONOMER SELECTED FROM THE GROUP CONSISTING OF ACRYLONITRILE, METHACRYLONITRILE, ALLYL CYANIDE, VINYLIDENECYANIDE, AND A-CYANOVINYLACETATE, SAID COPOLYMER CONTAINING CYANO GROUPS BEING A COPOLYMER PREPARED BY THE COPOLYMERIZATION OF A MONOMER SELECTED FROM THE GROUP CONSISTING OF ACRYLONITRILE, METHACRYLONITRILE, ALKYL CYANIDE, VINYLIDENECYANIDE, AND A-CYANOVINYLACETATE, AND A COMONOMER SELECTED FROM THE GROUP CONSISTING OF STYRENE, VINYL CHLORIDE, VINYLIDENE CHLORIDE, VINYL ACETATE, VINYL BENZOATE, BUTADIENE, METHYL ACRYLATE, METHYL METHACRYLATE, VINYLPYRROLIDONE, ETHYL METHACRYLATE, ACRYLAMIDE, ACROLEIN, METHYLVINYL-KETONE,ALLYLAMIDE,ALLYL ACETATE, ALLYL CHLORIDE, DIALLYLPHTHALATE, DIVINYLBENZENE, 2-VINYLPYRIDINE, 4-VINYLPYRIDINE, 2-METHYL-5-VINYLPYRIDINE, 5-ETHYL-2-VINYLPYRIDINE, 2-METHYL-5-VINYLPYRIDINIUMETHYL-BROMIDE, 4-VINYLPYRIDINIUM-ETHYL-METHYLSULFATE, DIMETHYLAMINOETHYLMETHACRYLATE, AND ALLYLPYRIDINIUMCHLORIDE; AND PREPARING A POLYVINYL ALCOHOL FIBER FROM SAID AQUEOUS SPINNING FLUID BY SPINNING WHEREIN SAID AQUEOUS FLUID CONTAINS A SUFFICIENT AMOUNT OF SAID DISPERSED WATER-INSOLUBLE POLYMERIC MATERIAL WHEREBY SAID PREPARED POLYVINYL ALCOHOL FIBER CONTAINS AN AMOUNT OF BASIC NITROGEN THAT IS AT LEAST ABOUT 0.05% DUE TO THE PRESENCE OF SAID POLYMERIC MATERIAL IN SAID PREPARED FIBER. 